Human factors help engineer better medical devices

Heinzelman: Human factors is a term used to describe a discipline that relates to the study of behavior and the way the human interfaces with equipment. With human factors, we are concerned about understanding the environment in which a device is to be used and the particular idiosyncrasies and constraints of that environment.

To take an example, if the medical device we are designing is used in surgical procedure and, it has to be designed to suit the skills and capabilities of the surgeon when used in that environment. In a sense, it should be a natural extension of the human body.

Q: How is designing equipment and devices for the medical industry different from designing products for other industries?

A: While the design effort for medical equipment requires many of the same disciplines and attitudes, one of the biggest differences is that consumer products are much more marketing driven while medical products are more task cumbersome performance driven. Having said that, it's important to note that cost is a very important consideration in designing medical equipment today.

Q: Is this industry more conservative than others?

A: Certainly the stakes are higher, so that, as designers of medical equipment, we need to be surer about the design. In other words, everything that we do must be reliable and safe, as well as repeatable from a manufacturing standpoint. There's not a lot of margin for error. In many of our projects, we have actually helped our clients design and create quality control equipment so that they can do 100% component testing.

Q: How important is product innovation in the medical industry?

A: Leading edge is very much a term that we apply to our design efforts-in fact it is key in the medical industry, especially in this age of laproscopic and minimally invasive procedures where every device is being downsized. In one recent project for a steerable catheter, we had to invent new steering and control mechanisms because the original handpiece was too big. We're also heavily involved in materials research.

Q: How has the technology you use in your design work changed, and what has been the impact?

A: We're big advocates of 3D engineering software. These tools give us much greater confidence in terms of the reliability of the parts that we are designing, so that at the point we get to an actual physical prototype we have a much better idea of how well it will perform. This has helped us reduce design cycle times tremendously, probably on the order of one-third to one-half, which is great because getting the task done quickly is an important requirement.

Q: What new developments can we expect to see in medical devices?

A: We really think, and are beginning to see, that information technology at the biological level is the direction that the industry is heading-not only in terms of the actual instrument design but also in gathering data through biological sensors, performing surgeries, and conducting diagnostic tasks.

Q: What is the key to the successful design of a medical device?

A: The most important thing to us is ensuring that the device itself does not in any way inhibit the user or surgeon from accomplishing the task at hand. While we do lots of simulations, all the computer power in the world is not going to tell us how things actually feel in the surgeon's hand, so we conduct a lot of field observations and prototype testing to get the design right. The true value of an industrial designer and a mechanical engineer in our field is to be able to go out and observe what happens in surgery and come back with creative ideas on how to improve the design. The two disciplines work together as a team to come up with the best possible designs.

Heinzelman joined Refac HumanFactors-ID as a staff designer after earning a BS in industrial design from Pratt Institute in New York and working briefly at Raymond Loewy International. In 1999 he was named president and CEO of the 27-year-old design and engineering company that was acquired by Refac in late 1997. In spring of 2000, Heinzelman was named senior vice president of Edgewater, NJ-based Refac and was elected to Refac's board of directors. During the more than 25 years he has spent at Refac HumanFactors, he has helped create numerous award-winning products, ranging from toothbrushes to surgical instruments, to consumer electronics products such as the VW New Beetle™ portable stereo. Heinzelman, who makes guitars in his spare time, has more than 25 U.S. patents in his name.

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